Energetic light pulses with short durations are used in numerous applications in science, industry, and medicine. For example, femtosecond lasers can allow probing of living structures without damaging the structures. In industrial applications, ultrashort laser pulses may be used for cutting, drilling, and ablating. These applications and new applications may be enabled by shorter pulses. New techniques and technologies are needed to generate ultrashort pulses that are extremely stable and robust, and which can be realized at an affordable cost.